Emissions Testing Checklist and Requirements for California

Up until more recent years, emissions and smog tests were performed on a majority of the vehicles on the road. Today, California is the only state to still actively do emissions tests on resident vehicles, and have very strict smog standards. A majority of California vehicles on the road are subject to bi-annual smog tests, but there are some exceptions depending on the vehicle. Hybrid cars, diesel engines, and vehicles built before 1975 are among the vehicles that are not required to submit for a smog test. In our blog this week, we want to give you an overview of what tests they run on your vehicle, and what exactly they are trying to look for through these tests.

• Gas Cap- Along with inspecting fuel lines, and other fuel delivery components, your gas cap will be checked to ensure the gasket is properly maintained and that the cap secures tightly.
• Ignition and vacuum system- Any fault in the ignition or vacuum tube system can result in poor engine performance, improper air/fuel mixture, or a check engine light. 
• Air/Fuel Ratio- This test involved using a test tube in your exhaust pipe while the var is running. It measures the air/fuel ratio which must be within a certain spec in order to pass emission standards.
• OBDII Reading- Prior to any inspection, the technician will run an OBDII code scanner to see if there are any check engine light faults. If a check engine light is present, the car will automatically fail the test.
•  Exhaust components- This includes things like checking the oxygen sensors, catalytic convertor, and resonator tube to ensure they are filtering out harmful toxins from your engine's exhaust. Typically they will let the car idle, and use a flashlight to detect any excess gas leaking from the exhaust.

Note that you are only required to submit to this emissions test if you decide to become a California resident in the future. Within 20 days of claiming your citizenship, the state requires you to transfer your registration as well as complete a smog test. For any further questions regarding specifics of the smog test, visit California's official website here.